1. Field of the Invention
This invention relates to containers and closures therefor designed to indicate the removal of the closure and to seal the container so that the purchaser may be assured that the contents of the container are as originally packed.
2. Description of the Prior Art
Prior structures of this type having break-away portions of a closure to indicate tampering are shown in U.S. Pat. Nos. 3,504,818 and 3,812,994. Sealing discs are illustrated in U.S. Pat. Nos. 2,180,199, 2,937,481, 3,352,268, 3,501,042, 3,805,993, 4,171,084 and 4,209,126. The sealing disc in U.S. Pat. No. 3,352,268 forms a flanged closure when applied to a container as does a sealing disc in U.S. Pat. No. 2,373,847.
The sealing discs in several of the prior art patents are adapted to be hermetically sealed to the container by incorporating a membrane adhesively affixed to the disc or alternately comprising a thermoplastic material which is compatible with and fusible to the material forming the container by heat directly or indirectly applied to the sealing disc.